Wireless cellular networks may include several cells, where each cell includes a base station that provides mobile communications and network services to mobile devices or user equipment (UE). In the wireless cellular networks, signals from one or more UEs in a cell coverage area of a base station are received by the base station, which then connects a call to a land-line telephone network and/or connects the UE to a network, such as the internet. In typical wireless cellular systems, a UE is serviced by one base station.
Wireless networks using the long-term evolution (LTE) standard may employ features, such as Carrier Aggregation (CA) and Coordinated Multi-Point Operation (CoMP), that allow UEs to be serviced by more than one base station. For example, when a UE works under the CA mode, the UE may be served by two or more cells, where one of the cells acts as a primary serving cell, and other cells act as secondary serving cells. Similarly, CoMP allows UEs to be served by more than one base station in order to enhance quality of service (QoS) on the perimeter of a serving cell.
Many wireless network applications use a location and/or position of a UE within a cell coverage area (e.g., power allocation algorithms, and the like). A difference between a signal reception (Rx) time and a signal transmission (Tx) time is used to determine a general location and/or position of a UE within a cell coverage area. An Rx and Tx time difference measurement may be referred to as a “round-trip propagation delay” or a “round-trip delay”. Currently, the LTE standard allows UEs to report Rx and Tx time difference measurements to a location server 200 via LTE positioning protocol (LPP). However, the Rx and Tx time difference measurements are only reported for a primary serving cell, not for secondary serving cells.
An accurate location of the UE may not be ascertained using the Rx and Tx time difference measurements from only one base station. Rather, the Rx and Tx time difference measurements from only one base station may only be used to determine that a UE is located within a cell coverage area. Therefore, other information such as Angle of Arrival (AoA) and/or signal strength measurements, such as receiver reference signal power (RSRP) and/or reference signals received quality (RSRQ) measurements are used to determine a UE's specific position within a cell coverage area. Because AoA, RSRP, and/or RSRQ are not direct distance measurements, there may be uncertainty in determining a UE's location and/or position.